Composite vector control method for permanent magnet synchronous wind generator

Abstract

The invention relates to a composite vector control method for a permanent magnetic synchronous wind generator, comprising the following steps of: controlling the size and the direction of a stator current vector value according to a mathematical model of the permanent magnet synchronous wind generator by utilizing the vector control method, and establishing a composite vector control strategy of the permanent magnet synchronous wind generator based on stator current orientation. Through the stator current orientation, a maximum torque current ratio control mode is adopted between the cutting speed and the turning speed of the generator so as to improve the generated power of a system; and a weak magnetic control mode with maximum power output is adopted between the turning speed and the limiting speed, therefore, the system efficiency is improved, and the system stability is ensured.

Description

technical field [0001] The invention relates to a control method of a generator, in particular to a compound vector control method of a permanent magnet synchronous wind power generator. technical background [0002] As we all know, wind power is the cheapest, most promising and inexhaustible green energy among renewable energy sources. At present, permanent magnet wind generators are used as a mainstream model of wind generators at home and abroad. With the development of power electronics technology and permanent magnet synchronous motor manufacturing technology, in the variable speed constant frequency wind power generation technology, the direct drive system using PMSG has the characteristics of omitting the gearbox and no direct coupling between the generator and the grid, so it has energy With the advantages of less loss, low maintenance cost, strong ability to resist grid fluctuations, and high reliability, it has become one of the most promising mainstream technologi...

AI Technical Summary

Problems solved by technology

However, in the wind power generation system, if only one vector control method is used, there are many disadvantages. For example, the control method based on the maximum torque-current ratio can only take care of below the turning speed, and using this method above the turning speed will cause the AC voltage of the converter to exceed the rated voltage. Value operation; On the contrary, the field weakening control method will lose a lot of power generation below the break speed

It can be seen that due to the large-scale fluctuation of the wind force, the traditional single-mode vector control method cannot meet the control requirements of the wind power generation system.

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